This set of FBI guidelines lays out the methods by which the FBI operates with regard to the terrorist threat. "The general objective of these Guidelines is the full utilization of all authorities and investigative methods, consistent with the Constitution and laws of the United States, to protect the United States and its people from terrorism and other threats to the national security, to protect the United States and its people from victimization by all crimes in violation of federal law, and to further the foreign intelligence objectives of the United States. At the same time, it is axiomatic that the FBI must conduct its investigations and other activities in a lawful and reasonable manner that respects liberty and privacy and avoids unnecessary intrusions into the lives of law-abiding people. The purpose of these Guidelines, therefore, is to establish consistent policy in such matters. They will enable the FBI to perform its duties with effectiveness, certainty, and confidence, and will provide the American people with a firm assurance that the FBI is acting properly under the law. The issuance of these Guidelines represents the culmination of the historical evolution of the FBI and the policies governing its domestic operations subsequent to the September 11,2001, terrorist attacks on the United States. Reflecting decisions and directives of the President and the Attorney General, inquiries and enactments of Congress, and the conclusions of national commissions, it was recognized that the FBI's functions needed to be expanded and better integrated to meet contemporary realities[.]"
U.S. Department of Justice: http://www.usdoj.gov